In Brown et al. U.S. Pat. No. 4,693,550 filed Mar. 11, 1985 and entitled Crimp Type Fiber Optical Connector, a fiber optic contact or connector is shown and described in which fiber optic cable has a free end which is stripped of insulation and is substantially surrounded by a sleeve member adjacent the free end. The sleeve member is proportioned to support the free end in abutting relation with the free end of another fiber optic cable. By this, and also by other, known designs of contacts or connectors for fiber optic cables, optical transmission can take place between the junction of the two fiber optic cables. If the ends of the fiber optic cables are properly finished and held by a connector system in tightly abutting relation, good optical transmission with low loss can be achieved across the junction between the two optic cables.
There is a need to assure in all circumstances that the free ends of the respective fiber optic cables are pressed together in firm contact to provide such good optical transmission of light across the junction and through the two cables. At the same time, the pressure must not be too great, to avoid scratching or other damage of the polished ends of the optic cables, which could reduce light transmission across the junction. Furthermore, this reliable, gentle but firm contact between the cable ends must be accomplished even though commercially manufactured parts of contacts normally exhibit some dimensional variance from part to part. It is of course a matter of great difficulty to obtain a precise, no-variance tolerance in manufactured parts. In many designs of contacts, the parts must be very precisely manufactured, with great difficulty, since the slightest variance can cause either excessive tightness of the bond between the optic cable ends, or the bond may be too loose, both of which circumstances are very undesirable.
In accordance with this invention, an optic contact is provided in which a firm, but not excessively tight, connection between optic cable ends can be provided despite the fact that parts in the connector are used that have a small variation in their dimensions from contact to contact. This of course makes it possible to mass produce contacts in accordance with this invention, with parts which are much less expensive than critically manufactured precision products that otherwise are needed in the optic contacts of the prior art, so that the overall cost of the optic contact may be reduced. Also, the contact of this invention exhibits improved reliability over prior art contacts having rigid parts of fixed, super precise tolerances.
Additionally, the optic contact of this invention provides firmer, more reliable optical connection over significant temperature variations which result in thermal expansion or contraction of its parts, and also under conditions of mechanical shock an vibration.